Drill bit



n. cAvvLERLY. DRILL B'ITl ALPPLICATVION FILED NOV. 6, 1920.

1,427,064, Patented Aug. 22, 1922.

7am/f @www Y INVENTOR ATTORNEY Unirse sTArgs yPasteur OFFICE.

RALPH CAVERLY, OF CHICAGO, ILLINOIS.

DRILL BIT.

Specification of Letters Patent.

Patented Aug. 22, y1922'.

u Application filed November 6, 1920. Serial No. 422,288.

ting position at predetermined intervals by.

suitable gearing, to effectively drill a well of uniform diameter with minimum effort.

A further obj ect of the invention is to provide a drill bit as specified, in ywhich the cutters are shaped to guide the cuttings inwardly to suitable suction pipes thereby preventingclogging of the drill due to accumulation of cuttings. l

Other objects of the invention will appear in the following'description taken in connection with the accompanying` drawing wherein: f

Fig. 1 is a longitudinal section through a drill showing the improved bit applied.

Fig. v2 is a bottom plan of the improved bit.

Fig. 3 is a horizontal section through the bit taken on line 3 3 of Fig. 1.

Fig. 4 is afdetailed vertical section through the port of the bit structure.

The improved drill bit is of the rotary type, including a drive shaft 1 which is rotatably supported in suitable bearing members 2 and 3. The bearing members 2 and 3 are rigidly mounted in a suitable casing 4 of the drill structure as disclosed in my companion application filed November 6, 1920- Serial No. 422,289. A stuiiing boX 5 is mounted in the bearing member2 to form a fluid tight joint about the rotary drive shaft 1 to prevent seeping of water or other liquid into the casing 4. The upper end of the shaft 1 has a gear 6 rigidly mounted thereon which is connected, by a suit-able gear train 7 to a prime mover 8 of any conventional form. The gearing 7 is adapted to reduce the speed of rotation and consequently increase the power applied to the shaft 1 through the gear 6.

A spider 9 is rigidly mounted upon the lower end of the shaft 1 and comprises a plurality of radiating arms 10, each of which is recessed vertically, asi at l1. The recesses 11 receive therein shafts 12, which are enlarged at their lowery ends as shown 'at 13 and have the cutting bits 14 formed integral therewith. As clearly shown in Fig. 4 of the drawing, the recesses 11 are longer than f the enlarged portions 13 of the shafts 12 and spiral springs 15 are mounted therein, being coiled about the shafts 12 and having ends engaging in suitable recesses 16 formed in` the arms 10 while their other ends engage in recesses 17 formed in the enlarged portions 13. Eachy of the shafts 12 has a pinion 18 rigidly mounted thereon, and meshing with a gear 19 rotatably mounted upon the drive shaft 1. Nuts 2O are mounted on the shafts 12 to prevent vertical movement of these shafts relative to the spider 9. The cutters 14 have their outer ends curved as shown at 21, their concave sides 22`form cutting edges and terminate in relatively sharp cutting edges 23 which, .when the cutters are in operative cutting position project beyond the. edge of the well case 24 and drill a hole slightly larger than the case 24 to permit the latter to move freely into a well being drilled. The cutters rotate in the direction indicated by the arrow A, and thus the cuttings made by the cutters will travel over the concave sides 22, inwardly towards the aXis of the shaft 1, and they will betaken up by the suction pipes 25, which are more specifically described in my companion' appli-` cation heretofore referred to.

The cutters 21 have heels 26 formed thereon which. extend inwardly towards the shaft 1 and are adapted to engage against the shaft to limit the relative rotation of the cutters 21 yand maintain them in the proper cutting position. These heel projections 26 have their upper surfaces recessed as at 27 to permit the `passage of the cutting ends of the cutters thereover, when the cutters are folded inwardly out of cutting position as indicated by the cutter 14 at the upper left hand side of Fig. 2 of the drawing.

They lower end of the drive shaft 1 is pointed as indicated at 28 to permit its free rotation in the bottom of the well being When the drill structure is lifted by the spiral springs 15. y

It is, of course, to be understood that the invention may be constructed in various other manners and the parts associated in different relations and, therefore, I do not desire to be limited in any manner except as set forth in the claims ,hereunto appended.

Having thus described my invention what I claim is 1. In a drill bit, a supporting spider, a plurality of cutters pivotally carried by said spider, means connecting; said cutters to cause simultaneous movement of the cutters, and a dri-ve shaft connected to said supporting,- spider;

2. In a drill bit, a drive shaft, a spider rigidly mounted on said drive shaft, a pluraljity of cutters pivotally carried by said spider, means connecting' said cutters for simultaneous movementinto or out of cutting positions, and means foi automatically removing' said cutters out of cutting positions at predetermined times.

3. In a drill bit, a drive shaft, a spider rig-idly mounted on saidvdrive sli-aft, a plurality of cutters carried by said spider for f pivotal movement relative thereto, heel. projections formed upon said cutters and adapted toy engage said drive shaft for limitin-g movement of the cutters relative to the spider.

4t. In a drilly bit, a drive shaft, a spider rigidly mounted on said drive shaft, a plurality ofcutters carried by said spider for pivotal movement relative thereto, heel projections formed upon said cutters and adapted to engage said drive shaft for limitingr movement of the cutters relative to the spider, said cutters provided With concave4 edges for L.guiding the cuttings inwardly towards the axis of said drive shaft.

5. In a drill bit, a drive shaft, a spider rigidly mounted on said drive shaft, a plurality of cutters carried by said spider for pivotal movement relative thereto, heel projections formed upon said cutters and adapted to engage said drive shaft for limiting movement of the cutters relative to the spider, sai'dcutters provided with concave edges for guiding the cuttings inwardly towards the axis of said drive shaft,- and gears connecting said cutters for simultaneous movement into and from cutting posit-ions.

6. In a'- drill bit, a drive shaft, a spider thereon, a plurality of cutters pivotally carried by said spider, means connecting' said cutters to cause simultaneous movement of the cutters, and means for limiting movement of the cutters relative to said spider.-

"T. In a drill bit, a drive shaft, a spider thereon, a plurality of cutters pivotally car'- ried by said spider, means connecting said cutters to cause simultaneous movement of the cutt rs into and out of cutting positions; means for automatically moving said' cutters out of cuit-ting positions at predetermined times, and means formed on said cutters for limiting' movement of the cutters relative to said spider'.

l8. In a drill bit, a drive shaft, a spider thereon, a plurality of cutters pi'ifotally car-A ried by said spider, means connecting said cutters for simultaneous movement into or out of cutting*` positions, means for auto-` matically moving said cutters out of cutting positions at predetermined times, and heel projections formed on said cutters forl en- `gage/ment With said drive shaft for limiting movement of the cutters 'relative to the spider.

In testimony whereof I afii'x my signature.

RALPH CVERLY. 

